Clinical effects of Sevoflurane

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Due to the preferable pharmacodynamics, Sevoflurane is the most favoured drug for the induction and maintenance of anaesthesia. Its low blood-gas partition coefficient helps to rapid alteration of the level of anaesthesia. 


CVS effects: 

→ Mild ↓ cardiac contractility (dose-dependent, equal to isoflurane)

→ Mild ↓ SVR (dose-dependent, equal to Halothane)

→ Mild ↓ BP (dose-dependent, most least compared to others)

→ Minimal effect on HR

→ May cause prolongation of the QT interval 

→ Not associated with coronary steal 

→ Doesn't sensitize the myocardium 

→ No effect on splanchnic blood flow 


Respiratory effects:

→ Non-irritant 

→ Dose-dependent Tidal volume depression (less than Isoflurane, equal to Halothane) 

→ ↑ RR (equal to Isoflurane, more than Halothane) 

→ ↓ MV causing ↑ PaCO2

→ Depression of hypoxic and hypercapnic ventilatory drive 

→ Inhibition of hypoxic pulmonary vasoconstriction 

→ Bronchial smooth muscle relaxation and reversal of bronchospasm 


CNS effects:

→ Effect on cerebral autoregulation is less pronounced than Isoflurane 

→ > 1.5 MAC may impair cerebral autoregulation 

→ Minimal effect on ICP at 0.5 - 1.0 MAC due to preservation of autoregulation 

→ Slight in CBF in normocarbia 

→ No excitatory effect on EEG

→ Potentiate neuromuscular blocking drugs 

→ Compared to Halothane, higher incidence of postoperative agitation and delirium in children 


Neuromuscular:

→ Dose-dependent muscle relaxation 

→ Can produce adequate relaxation for intubation 


Hepatic:

→ Maintain total hepatic blood flow 

→ No immune-mediated hepatic toxicity 


Renal: 

→ Barium hydroxide and Sodalime may degrade Sevoflurane and may produce compound A

→ No proven renal toxicity

→ Preserve renal blood flow 


Others:

→ Causes uterine relaxation 

→ PONV


Reference - 

Pharmacology Of Inhalational Anaesthetic Agents – Part 2

Pharmacology for anaesthesia and intensive care, 4th edition 

Smith and Aitkenhead's Textbook of Anaesthesia, 7th edition 

Morgan and Mikhail's Clinical anesthesiology, 6th edition 

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